Carburetor needle-valve and choke-valve controlling device



H. FORD April 28,1931;

CARBURETOR NEEDLE VALVE AND CHOKE VALVE CONTROLLING DEVICE Original Filed June 16, 1928 A TTORNEK I Patented Apr. 28, 1931- UNITED STATES PATENT OFFICE HENRY FORD, OF DEAL'RIIBORN, MICHIGAN, ASSIGNOR TO FORD MOTOR COMPANY, OF

DEARIBORN, MICHIGAN, A CORPORATION 01 DELAWARE CARBURETOR NEEDLE-VALVE AND CHOKE-VALVE CONTROLLING DEVICE Original application filed June 16, 1928, Serial No. 285,907. Divided and this application filed August 28,

. 1929. Serial No. 388,951.

provide a carburetor made from two castings which are so shaped that they may be jointed together at approximately the middle horizontal plane of the carburetor and secured together by a single bolt whereby the assembly and disassembly of the carburetor for repair or adjustment may be greatly simplified.

Still a further object of my invention is to provide a carburetor having two fuel jets for normal running operation one of which has a practically unrestricted flow during the low vacuum period of carburetor use and a restricted flow during high vacuum and the other has a restricted flow at all times whereby plenty of fuel will be supplied to the throat of the carburetor when the engine is running at low speed but the flow of the fuel at high engine speed will not be increased out of proportion to the increased fuel requirement.

Still a further object of my invention is to provide in combination with such a car,- buretor a manually controlled fuel supply which may be finely metered ,to adapt the carburetor to various engines or various climatic or fuel conditions.

Still a further object of my invention is to provide in combination with such a carburetor, a compensating well whereby a reserve supply of fuel always may be available when the engine is changed from an idling to an operating speed.

Still a further object of my invention is to provide a controlling device for a carburetor of the type specified wherein a single control rod may be used for operating both the manually controlled fuel supply and for operating a choke valve.

Still a further object of my invention is to provide such a carburetor control rod wherein rotation thereof will adjust the needle valve and reciprocation thereof will operate the choke valve but either rotation or reciprocation thereof will not affect the possibility of simultaneously or independ-' ently adjustin the choke and needle valves. Still a further object of my invention is to provide such a controlling device wherein the parts may be very readily made on the production basis and their assembly or disassembly may be readily accomplished.

With these and other objects in view my invention consists in the arrangement, construction and combination of the various parts of my improved carburetor, as described in the specification, claimed in the claims, and illustrated. in the accompanying drawings, in which:

.Figure 1 shows a diagrammatic and schematic view of my improved carburetor showing the operation of the various parts thereof.

Figure 2 shows a vertical longitudinal central sectional view through my improved carburetor.

Figure 3 shows a horizontal sectional view taken on the line 33 of Figure 2.

Figure 4 shows an elevation of my improved carburetor illustrating its manner of installation on an engine, and

Figure 5 shows a sectional View taken on the line 55 of Figure 4.

Referring to the accompanying drawings, I have used the reference numeral 10 to indicate generally the casting forming the upper portion of my carburetor and the reference numeral 11 to indicate generally the casting forming the lower portion of my carburetor. These two parts are secured together by a single bolt 12 which extends up through the lower casting 11 and is threaded into the upper casting 10. The two castings have a liquid tight joint formed therebetween by means of the gasket 13. The bolt 12 is provided with a lock washer 14 which prevents it from unscrewing accidentally. At the right hand end of this casting 10, it is provided with an upwardly opening cup or chamber 15 which forms the bottom and sides of the float chamber for my improved carburetor.

A metallic float 16 is disposed in this chamber and supported on a yoke 17 which is pivoted at 18 to the yoke 19 which is suitably secured to the bottom of the upper casting 10. From the foregoing it will be seen that the bottom and sides of the float chamber are formed from a single casting but that the float is supported by the upper casting which is separable from the lower casting, so that the separation of these two castings does not necessitate any alteration or movement of the float mechanism but at the same time the construction makes said mechanism readily accessible for any inspection or adjustment.

The valve assembly is secured in a bore 20 in the upper casting 10 directly over the float 16 so that when the latter is in its upper position, the valve will be closed. This assembly consists of a sleeve 21 having a valve 22- mounted therein for vertical movement whereby the extending end of the valve 22 may be operated by movement of the float 16 to admit fuel to the float chamber to fill the latter to a predetermined level. The sleeve is secured in place in the casting in any suitable manner as by means of threads 23 so that the assembly may be removed for inspection or replacement.

A horizontal duct 24 is formed in the upper casting 10 to communicate with the vertical bore 20 and extends to the right hand of this casting as will be noted by Figure 2. The outer end of this horizontal bore 24 is threaded so that a screen assembly may be screwed into the bore. This assembly comprises'the hexagonal wrench engaging head 25, the threaded portion 26, a shank 27, a cylindrical screen 28, and an end member 29, these parts being arranged from right to left in the order named. A gasket 30 ismounted between the casting 10 andthe head 25 to secure a fuel tight joint between the parts.

The opening between the duct 24 and the bore 20 is somewhat restricted and the cylindrical screen 28 is of slightly less diameter than the major portion of the duct 24 so that fuel which enters the duct 24 will flow through the screen 28 from the outside thereof to the inside thereof and then through the end 29 into the bore 20. This end 29 is of such dimensions and is so placed that it will prevent fuel received into-the bore 24 from entering the bore 20 except after it has passed through the screen 28. From the foregoing description it will be seen that the fuel filtering screen used in connection with my improved carburetor is a compact assembly which may be installed or removed as a unit from the upper casting member.

Fuel is supplied to the duct 24 by means of a fuel supply pipe 48 which is connected by a pack nut 49 with an elbow 50 which screws into an opening in the casting 10 which communicates with the duct 24.

The air entering my improved carburetor to be mixed with vaporized liquid fuel passes through the horizontal air inlet passage 31 and then turns and passes upwardly through a venturi 32 into a vertical mixture passage 33 in the upper casting 10, from which it passes into an engine intake manifold 34. The upper casting 10 is secured to this intake manifold by means of bolting flanges 35 which extend from the manifold 34 and casting 10, these parts being held together by the cap screws 37 and a liquid tight joint being insured by the gasket 36. The air which is supplied to the air inlet passage 31 is drawn through an air pipe 38 whichmay be connected to any suitable supply of air such for instance as an air cleaner or a stove for heating the intake air by means of the exhaust manifold heat. The air inlet passage is provided with a choke valve 39 which is mounted on a shaft 40 which extends through the air inlet passage 31 so that the amount of air admitted through the air inlet passage to the Venturi 32 may be restricted to thereby increase the suction on the fuel jets. A throttle valve 41 is mounted in the fuel passage 33 and supported by a shaft 42 in said passage.

This shaft 42 extends outwardly through the wall of the casting 10 and carries an actuating arm 43 at the outer end thereof designed to be connected through a ball joint 44 with a carburetor control rod 45. An adjustable stop screw 46 is mounted on the casting 10 in position to co-act with a lug 47 extending from the arm 43 whereby the closing movement of the throttle valve 41 may be limited to thereby insure the proper position of the throttle valve 41 when the engine is idling.

A Venturi structure of my improved carburetor is formed by slipping a sleeve into the mixture passage 33, this sleeve having a shoulder 52 near the lower end thereof which contacts with the lower surface of the gasket 13 to limit the movement of the sleeve 51 into the mixture passage 33. The lower end of the sleeve 51 below the shoulder 52 is slotted at the opposite sides thereof to receive the arms 54 which extend from the auxiliary demountable sleeve 55. These arms 56 also bear against an annular flange or shoulder 56 in the lower casting 11 whereby the clamping of the casting 10 and 11 together by means of the screw 12 may clamp the Venturi assembly comprising the sleeves 51 and 55 between the shoulders 56 and the gasket 13. This makes it possible to assemble and disassemble the Venturi structure by separating the castings 10 and 11 and then dropping the sleeves 51 and 55 into their place or lifting them out of their place.

.The inner-engaging portions of the arm 54 and the slot 53 are such that the parts cannot be put together the wrong way and of course the sleeve 51 cannotbe put into the casting 10 the wrong way because the lower end is larger than the upper end due to the shoulder 52. I

Whenmetered jets are provided for atomizing the fuel in connection with carburetion, it has been found that. a metered jet which is sized to giving the correct mixture when there is a low vacuum in the carburetor will not give a proper mixture when there is a high vacuum in the mixing chamber as a jet which gives the proper fuel mixture for low vacuum will give too much fuel under high vacuum conditions. On the other hand, a jet metered for correct mixture under high vacuum will not give enough fuel for low vacuum conditions. In my improved carburetor, I have therefore provided a single metered jet 57 which gives just a part of the fuel required for operating the engine at all speeds. This jet being of the ordinary metered type will of course increase its fiow with varying vacuum conditions so as to give more fuel at higher engine speeds and relatively less fuel at lower engine speeds. This jet 57 is connected with the carburetor drain well 58 which is normally sealed by a cap screw 59 and a gasket 60. A passageway 61 is drilled between this drain well 58 and the float chamber 15 to supply the fuel for the jet 57.

A compensating jet 62 also extends up to the sleeve 55. This jet 62 communicates through the passageway 63 with a com pensating well 64 which is formed in the casting 11. This well is connected through a metered hole 65 with the float chamber 15. From the foregoing it will be seen that fuel may flow quite freely from the well 64 through the passageway 63 and out of the jet 62 as these passageways are relatively large and the fuel may consequently be drawn therefrom by relatively low vacuum. As the speed of the engine is increased the fuel in the well 64 is drawn out by the vacuum in the jet 62 more rapidly than it may flow by gravity through the hole 65 until the fuel in the well 64 lowers even with the passageway 63, at which time the fuel supplied by the jet 62 is limited to the amountwhich may flow by gravity through the opening 65. In other words this compensating jet 62 furnishes a relatively large supply of fuel with relatively low vacuum conditions in' the manifold for low engine speeds but limits the total amount of fuel which may be drawn therethrough at high engine speeds due to the metered hole 65.

From the foregoing it will be seen that the jets 57 and 62 automatically tend to proportion the fuel supplied thereby to the vacuum created by the action of the engine.

' That is, the jet 57 tends to feed more fuel in proportion as the engine speeds up thereby compensating for the additional fuel required while the jet 62 tends to feed more fuel in proportion while the engine is running slowly or accelerating from idling but the total amount for this et is limited to a predetermined maximum by the metered opening fuel from the duct 67 which in turn communicates with the float chamber 15 and the valve 68 may be adjusted to control theadditional fuel fed through the duct 66 into the jet-62. From the foregoing it will be seen that the needle valve 68 may be manually adjusted to supply additional fuel to the engine when same is desired on account of variations in temperature, atmospheric conditions, or engine requirements.

An idling jet 69 is "mounted in the casting 10 and extends down int-o the well 64. This idling jet 69 extends down into the pocket at the bottom of this well which is below the level of the duct 63 and the metered hole 65 so that there is always gas in the bottom of the well under all carburetor conditions as the duct 63 will not draw the gas out of the bottom of this well 64 far enough down to drain the well.

A manually adjustable air inlet 70 is formed in the casting 10 and designed to admit air to a mixing chamber 71 which surrounds the jet end of the idling jet 69. The amount of air admitted is adjusted by the relatively large needle valve 93. The mixed air and fuel from the chamber 71 passes through the priming hole 72 into the top of the fuel passage 33 at approximately the level of the throttle valve 41. It will thus be seen that the vacuum created in the manifold by the closing of the throttle valve 41 will suck up air and fuel from thechamber 71 into the manifold. This inlet of fuel provides for the supplying of the engine with the idling mixture. Of course the closing of the throttle cuts the vacuum in the fuel passage 33 of the air inlet 31 down to practically nothing so that substantiall no fuel is taken from the jets 57 and 62 during the time that the throttle valve is closed to cause the engine to idle. It may be mentioned here in passing that the air inlet 70 for the idling mixture also serves to admit air into the well 64 to mix with the fuel taken therefrom by the jet 62 at high speeds of the engine.

The needle valve 68 is mounted in a laterally extending portion of the casting 11. A relatively large well 74 is drilled down into the extension 73 and the top of this well is closed by a gland nut 75 which is screwed down into the top of the well by means of a pipe thread 76. The needle valve 68 passes through this gland nut 75 and is threaded at 77 to cause it to be vertically adjustable in this gland nut so that the point of the valve 68 may be adjusted to meter or shut off the fuel supplied through the duct 66. A sleeve 78 is formed integral with the gland nut 75 and extends upwardly therefrom. The valve 68 also has an extension 79 which extends up through this sleeve 78 but this extension instead of being round like the balance of the valve 68 is half round as clearly appears in Figure 5.

An intermediate connecting assembly is formed to connect the combined choke and carburetor adjusting rod 80 with the needle.

valve 68 and the choke valve operating shaft 40. This assembly comprises a rod 81 which has its lower end half round and of such diameter that it may slidingly extend into the sleeve 78 and co-act with the half round end 7 90f the needle valve 68 to fill the interior of the sleeve 78 whereby rotation of this rod 81 will-rotate the needle valve 68 but the reciprocation of this rod 81 within the sleeves 78 may be permitted without affecting the rotary driving connection between the rod 81 and the valve 68. A sleeve member 82 is pinned as at 83 to the rod 81 and extends down over the sleeve 78 to have a telescopic connection therewith. In other words the sleeve 82 can rotate relative to the sleeve 78 and slide thereon.

A pair of flanges are formed at the lower end of the sleeve 82 so that a channel 84 is formed between these flanges which is designed to receive the inwardly extendingpin 85 on the free end of the arm 86 which is fixed to the choke valve operating shaft 40 by the nut 87.

From the foregoing description it will be seen that rotation of the rod 81 rotates the valve 68 to adjust same while reciprocation of the rod 81 will swing the arm 86 to operate the choke valve 89. The driving connection between the rod 81 and the valve 68 remains the same however, in any of the po-' sitions of the rod 81. In other words rotation and/or reciprocation of the rod 81 will rotate the valve 68 and/or operate the choke valve 39. The adjacent ends of the connect ing rod 81 and the operating rod 80 are formed with complementary shapes whereby when these complementary shapes are moved into engagement so that longitudinal and rotary movement of the rods relative to each other is prevented but they may be moved laterally out of engagement with each other.

These complementary shapes form a readily detachable scarf joint connection which may be instantly detached by raising the sleeve 90 and moving one of the members laterally. The end portions of each of the members 80 and 81 are machined fiat on one side, as at 94, about one-third of the rod section being removed. Between these ends 94 and the body of the respective members, a still further flatted portion is machined, as at 95, there being about two-thirds of the rod section removed from these sections. To assemble this device each end 94 is inserted into the flatted portion 95 of the opposite member thereby interlocking the members against longitudinal as well as rotary relative movement. The advantage of this structure arises because no pins, rivets, screws or the like are required to non-slideably and nonrotatably secure the members together.

As is usual in connection with such operating rods, this rod 80 passes through a dash member 89 and a sleeve 90 is slidably mounted on the rods 81 and 80 adjacent to the sleeve 82 and is of such dimensions that when these two parts interlock at their adjacent ends, then that sliding the sleeve 90 down over the interlocked portions will prevent movement of these rods relative to each other as the interlocking portions prevent rotary or longitudinal movement and the sleeve prevents lateral movement of the rods relative to each other.

The sleeve 90 is yieldingly urged into its position which holds the rods interlocked with each other by a spring 91 which extends between the dash 89 and the flange 92 on the sleeve 90. This spring 91 has the double function of holding the sleeve'90 in place so that the rods 81 and 80 will be locked together and also of tending to press the operating rod 80 to its lower position whereby it yieldingly urges the choke valve 39 to its open position.

From the foregoing it will readily be seen that the joint between the rods 80 and 81 is such that these two parts may be readily con nected and disconnected if the carburetor is to be removed as these rods may be disconnected by simply pulling up the sleeve 90 against the pressure of the spring 91 which permits the rods 80 and 81 to move apart laterally from eachother. When these parts are again connected, the spring 91 has the further function of holding the choke valve open unless the rod 80 is held in position to move the choke rod to some other position.

Among the many advantages derived from the use of my improved carburetor, it should first be pointed out that I have provided means to cause the carburetor to automatical- .1y compensate for varying vacuum conditions in the mixing chamber due to varying engine speeds and at the same time I have provided a manual metering control for supplying additional fuel to make the carburetor manually adjustable for climatic, temperature or en ine conditions.

till a further advantage results from the two part casting construction used in connection with my carburetor which seals in the liquid fuel against leakage much more easily and at the same time permits ready separation of the carburetor parts for repair or adustment and to permit draining of the caruretor. Still a further advantage results from the use of my im roved carburetor with the control rod which oth adjusts the needle valve and closes the choke valve.

In this improved mounting, the sleeve 90 and spring 91 have the double function of permitting ready removal of the parts for repair or adjustment and of normally holding the choke valve in its 0 en position. Still a further advantage 0 this choke valve mounting construction is that the parts are readily manufactured on a production basis but are extremely durable, strong and not at all liable to get out of order.

Some changes may be made in the arrangement, construction, and combination of the various parts of my improved device without departing from the spirit of my invention, and it is my intention to cover by my claims, such changes as may reasonably be included within the scope thereof.

This application is a division of my pending application Serial Number 285,907, filed June 16,1928.

I claim as my invention:

1. In a carburetor needle valve and choke valve controlling device, an operating rod adapted to extend through the dash, an operating member, means for operatively connecting said member with the needle valve and choke valve so that rotation of the member may rotate the needle valve and reciprocation of the member may operate the choke 0 valve, the parts being so connected that the reciprocation or rotation of said member will not disconnect it from either the needle valve or choke valve, interlocking faces on said member and rod at their adjacent ends, a sleeve adapted to receive said ends and prevent disengagement thereof, and a spring extended between said dash and sleeve adapted to hold the sleeve in position to keep the member and rod in engagement with each other and to move the member to position to hold the choke valve open.

2. In a carburetor needle valve and choke valve controlling device, an operating rod extending through the dash, an operating member detachably secured to said rod, a sleeve secured to the carburetor, a needle valve threaded into said sleeve having its outer end slidably and non-rotatably secured to the operating member within said sleeve, and means secured to the operating member so that reciprocation thereof will operate the choke valve.

3. In a carburetor needle valve and choke valve controlling device, an operating rod extending through the dash, an operating member, a scarf joint connection between said rod and member, a sleeve encircling said joint, a spring extended between said dash and sleeve so that said joint may be readily detachable, a sleeve secured to the carburetor, a needle valve threaded into said sleeve having its outer end slidably and non-rotatably secured to the operating member within 65 said sleeve, and means secured to the operating member so that reciprocation thereof will operate the choke valve.

4. In a carburetor needle valve and choke valve controlling device, an operating rod extending through the dash, an operating member detachably secured to said rod, a needle valve telescopically secured to said operating member, a sleeve secured to the operating member above said telescopic connection, a choke valve arm, and an annular groove formed on said sleeve adapted toco act with said arm so that reciprocation-of said sleeve will operate the choke valve and rotation of said sleeve will not operate the choke valve.

August 22, 1929-.

. HENRY FORD. 

